(i) Technical Field
The invention relates to an image carrier having a photosensitive layer on a surface of which an electrostatic image is formed and a process cartridge and an image-forming apparatus containing the image carrier.
(ii) Related Art
Image-forming apparatuses such as a printer and a copying machine have been widely used, and the technology concerning various components for such image-forming apparatuses are also widely known. In image-forming apparatuses in electrophotographic process, among many image-forming apparatuses, a printing pattern is often formed by charging an image carrier such as a photoreceptor using an electrostatically charging unit and forming an electrostatic latent image different in electric potential from that of environment on the charged image carrier, and the electrostatic latent image thus formed is developed with a developer containing a toner and finally transferred onto a recording medium.
In an image-forming apparatus in the electrophotographic process, the image carrier has an important role of holding the original image,i.e., an electrostatic latent image, and allowing development of the electrostatic latent image. Recently, various process cartridges containing an image carrier and other components for image-forming apparatus such as an electrostatically charging unit are more readily available in the market. Such a cartridge is easier, for example, in maintenance, because a user can install multiple components including an image carrier in an image-forming apparatus together by installing a process cartridge in the image-forming apparatus.
In such a process cartridge, the performance of an image carrier may vary according to its storage condition before installation in image-forming apparatus. For example, when a process cartridge is stored under the environment subjected to frequent vibration, locally charged regions are formed on the image carrier surface by abrasion between the electrostatically charging unit and the image carrier and. As a result, irregularity in electrostatic property may occur on the image carrier surface. When the image carrier is used for image formation while there is irregularity in electrostatic property as described above, there may be some image-quality defects in the formed image, for example, caused by irregularity in density.